Polyamide copolymers from hexamethylene diammonium adipate/terephthalate and a third polyamide forming reactant

ABSTRACT

A ternary fibre forming copolyamide consisting essentially of the polymeric condensation product of (1) at least 50 percent by weight of hexamethylene diammonium adipate, (2) 20-40 percent by weight of hexamethylene diammonium terephthalate and (3) 2-20 percent by weight of a third polyamide.

United States Patent Edgar et a1.

[ Dec. 16, 1975 POLYAMIDE COPOLYMERS FROM HEXAMETHYLENE DIAMMONIUM ADIPATE/TEREPHTHALATE AND A THIRD POLYAMIDE FORMING REACTANT Inventors: Owen Burchell Edgar, Manchester;

Michael Richard Yates, Leeds, both of England Imperial Chemical Industries Ltd., London, England Filed: 0a. 18, 1973 Appl. No.: 407,679

Related US. Application Data Continuation of Ser. No. 201,966, Nov. 24, 1971, abandoned, which is a continuation of Ser. No. 578,521, Sept. 12, 1966, abandoned.

Assignee:

Foreign Application Priority Data Sept. 16, 1965 United Kingdom 39587/65 US. Cl 260/78 R; 161/177; 260/78 A; 260/78 L; 260/78 S; 264/177 F Int. Cl. .....................C08G 69/26; C08G 69/14; COSG 69/08 Field of Search 260/78 R, 78 A, 78 L OTHER PUBLICATIONS Oronite Chemical Co. Oronite Isophthalic; Apr. 1955, Bulletin No. 10.

Primary ExaminerHarold D. Anderson Attorney, Agent, or FirmAndrew F. Sayko, Jr.

[57] ABSIRACT A ternary fibre forming copolyamide consisting essentially of the polymeric condensation product of (1) at least 50 percent by weight of hexamethylene diammonium adipate, (2) 2040 percent by weight of hexamethylene diammonium terephthalate and (3) 2-20 percent by weight of a third polyamide.

3 Claims, 2 Drawing Figures US. Patent Dec. 16, 1975 3,926,924

M Attorney POLYAMIDE COPOLYMERS FROM HEXAMETHYLENE DIAMMONIUM ADIPATE/TEREPHTHALATE AND A THIRD POLYAMIDE FORMING REACTANT.

This application is a continuation of application Ser. No. 201,966 filed Nov. 24, 1971, now abandoned, which is in turn a continuation of Ser. No. 578,521 filed Sept. 12, 1966, now abandoned.

The present invention is concerned with polyamide copolymers and in particular with copolymers of polyhexamethylene adipamide and polyhexamethylene terephthalamide containing a third component (such as polyepsilon caprolactam or polyhexamethylene isophthalamide).

Because of its desirable properties polyhexamethylene adipamide (6.6 nylon) yarn has found wide application in the textile field especially in apparel fabrics. The softening point of the polymer is sufficiently high to prevent undue damage to fabrics by normal domestic washing and ironing but not sohigh as to produce difficulties at spinning resulting from degradation for example. However for some spinning processes e.g. in the manufacture of filaments having a non-circular cross-section it is desirable that the polymer should have a higher melt viscosity but without any substantial change in softening point.

The melt viscosity of nylon 66 can, of course, be raised by raising its molecular weight, but attempts to raise the molecular weight to any substantial degree frequently result in the occurrence of undesirable cross-linking and discolouring of the polymer.

Alternatively the melt viscosity of nylon 66 can be raised without raising the molecular weight by the incorporation therein of a second high melt viscosity polymer to form a copolyamide. A suitable polyamide for this purpose is polyhexamethylene terephthalamide (6.T nylon). However, although the melt viscosity of 66 nylon can be raised in this manner only a limited amount of 6.T nylon, about 18% can be added before there is an undesirably large increase in softening point of the copolymer in excess of 265C which makes for problems in spinning.

We have now found that high melt viscosity copolyamides having softening points not substantially greater than 66 nylon i.e. less than 265C, comprising a major proportion, i.e. at least 50%, of 66 nylon and at least 20% of 6.T nylon canbe obtained by adding a third polyamide component to the 6.6/6.T copolymer to depress the softening point. The third polyamide component constitutes a minor proportion of the copolyof polyhexamethylene adipamide together with at least 20% of polyhexamethylene terephthalamide and a minor proportion of a third polyamide.

Preferably the copolyamide should contain 20% to 40% by weight of polyhexamethylene terephthalamide and 2% to 20% and even more preferably 5% to 10% by weight of the third polyamide.

As especially useful third component polyamides for the ternary copolymer there may be mentioned, by way of example only, polyepsilon caprolactam and polyhexamethylene isophthalamide. Polyhexamethylene sebacamide, polyhexamethylene suberamide and po- 1y(w-a min0 undecanoic acid) may also be used as the third component.

The high melt viscosity copolyamides of this invention are particularly useful in spinning filaments having non-circular cross-section, e.g. a trilobal or star-shaped cross-section, by melt extrusion through profiled spinneret orifices. The filaments so formed tend to retain more faithfully the shape imparted to them by the orifices than do filaments formed from polyamides or copolyamides of lower melt viscosity, which filaments tend to revert to a circular cross-section.

The 6.6/6.T nylon copolymer containing polyhexamethylene isophthalamide (6.i.P. nylon) as the third component is of particular value since it has both a high melt viscosity and also provides filaments having a relatively high initial modulus.

The following examples illustrate the invention but are in no way intended to be limitative thereof. In these examples the percentage compositions in all of the copolyamides were calculated as weight percentages on the fininshed polymers.

EXAMPLES 1 & 2

grns. of mixed salts of hexamethylene diarnmonium adipate hexarnethylenediammonium terephthalate and hexamethylene diammonium isophthalate in the correct proportions by weight to yield copolymers of the desired composition were charged into carius tubes together with 10 ml. and 3.5 m1. of distilled water and 1.0 and 0.55 moles of acetic acid stabiliser respectively. The tubes were purged free of oxygen, evacuated, sealed and heated in example 1 for 6 hours at 230C, and in example 2 at 280C for 1 hour plus 220C for 3 hours, in a rocking furnace. The half made polymers were subsequently finished in a 2 inch diameter tube equipped with a stirrer and nitrogen bleed at 285C for 40 minutes in example 1 and 285C for 1 /2 hours, in example 2. The resultant copolymer properties are listed in Table 1.

TABLE 1.

Example Properties of 66/6.T/6iP copolymer Copolymers, wt.% ratios of 66/6.T/6iP Amine end groups Carboxyl end group equivalents per 10 gms Acetyl end group equivalents per l0 grns Melt viscosity Softening point 44.0 3370 poises Melt viscosity was measured using an Epprecht viscometer under an atmosphere of steam at 290C. The viscosity reading was taken 1 hour after the polymer had been introduced into the apparatus.

Softening point was determined by means of a Vicat penetrometer using a load of 200 gms.

The copolymers were spun on a rod spinner at 300C.

TABLE 5 Properties of hexalobal 66/6176 (61.7/33. l/5.2)drawn yarn using a 5 circular hole spinneret and drawn over a hot Drawn denier l06.6 plate at 100C and 180C at draw ratios f 4.5 and 5.75 3: 3 to break W 3 3 respectively. The properties of the drawn yarns are Initial modulus g/d/100% given in Table 2 below. extension TABLE 2 Physical properties of drawn 66/6.T/6iP copolymer Example 1 2 Copolymer wt.% ratios of 6.6/6.T/6iP 58/3l.5/10.5 72.8/2l.9/5.3 Denier 31.5 Tenacity (gld) 4.57 9.3 Extension to break 21.9 16.3 Initial modulus (g/d/IOO extension) 43 41.3 Boiling water shrinkage 14.4

EXAMPLE 3 A cross section of filaments taken from this yarn is shown in FIG. II good shape retention was again obl707.l gms. of mixed salts of hexamethylene dlam- Laihed monium adlpate hexamethylene dlammomum tere- The copolyamides of this invention may include the phthalate and caprolactam, propomons to glve a usual additives for polyamides, including delustrants, 61 7/33 1/5 2 66/6 T/6iP 1 t th with t COPO ymer 5 pigments antloxldents or light stablllsers without mate- 1000 gms of water and 3.25 gms of acetic acid were riahy affecting the properties thereof heated together with stirring in an autoclave under an If desired the copolymer may be spun as one comp0 atmosphere of nitrogen. The temperat of the auto nent of a heterofilament, another component preferaclave was raised to 215C and the pressure to 250 b] havin a higher shrihka e to ield crimped or y g g Y p.s.l.g. during a period of 1 hour 40 minutes. The prescrimpahle filamehts sure was maintained at this level for 1 hour during The copolymer is also particularly Suitable f the whlch the utemperflmre rose to and manufacture of hollow filaments, its high melt viscosity feduced dmng the next h wlth a f resulting in a reduced incidence of collapsed filaments. increase in temperature to 282C. Finally the mixture was kept under steam at atmospheric pressure for 1 EXAMPLE 4 hour at 295C and then extruded into cold water. 715 parts b weight of hexamethylene diammonium The properties of the copolymer are given in Table 3 adipate, 379 parts by weight of hexmhethylehe s, belowphthalate, 5.2 parts by weight of caprolactam, 0.209 TABLE 3 40 parts by weight of acetic acid stabiliser and 75 parts by weight of water were heated together in a sealed auto- Physical ififijfi (wail/5'2) clave. When the pressure in the autoclave reached 250 Amine end mu e uivalems p.s.i. steam was allowed to excape to maintain the presper 0 p q 449 sure at that level whilst the temperature was raised to Carbol yl en gr p q i l n 245C The pressure was then allowed to fall to atmogg fl ggg 3x poises spheric over a period 0t: 1 hour, the temperature rising I at 290C to 265C and the heating continued under steam at Smemng 255 atmospheric pressure for a further 7% hour with a further increase in temperature to 272C. The resultant 5 polymer was extruded into a ribbon, quenched and cut Samples of this polymer were charged to a '5 inch 0 into chips The polymer was Spun into a 20 trilobal Screw exmider and extruded P 6 filament yams filament yarn by extrusion through spinneret orifices "P spmneret pletes Y'shaped 6 having three limbs Of length 0.020 inch and width pomted star'shaped cfnfices to gwe mlobal and hexalo 0.004 inch and subsequently cold drawn. Details of the ba] filaments respectively. The yarns were drawn overa polymer Spun and drawn yam properties and of the hot plate at 100C. at a draw ratloof 4.25. The proper- Spinning and drawing conditions are given in Table ties of the drawn yarns are given in Tables 4 and 5. TABLE 4 TABLE 4 Conditions of spinning and drawing and Properties of trilobal 66/6.T/6 (6l.7/33.1/5.2) properties of 66/6.T/6 trilobal yarn.

drawn yarn 0 Polymer properties Drawn denier 103.5 Wt. percentage of components in Tenacity (g/d) 4.3 finished polymer (6.6/6.T/6) 6l.5/33.4/S.2 EXtenSlOn break 39.3 Melt viscosity of polymer 1600 poises Initial Modulus (g/d/ 100% ext.) 26.2 Spinning conditions Speed, f.p.m. 1255 Temp. C 288 Spun yarn denier 820 The cross-section of filaments taken from the yarn is Drawing conditions shown in FIG. 1 from which it can be seen that excelpeed, f.p.m. 608 lent shape retention was obtained. Relative viscosity 40.0

TABLE 4.-continued Conditions of spinning and drawing and properties of 66/6.T/6 trilobal yarn.

Drawn yarn properties Modification ratio is the ratio between the escribed ans inscribed circles which can be drawn around a cross-section of the filaments constituting the yarn.

Polyhexamethylene adipamide having softening point of 255C and a melt viscosity of 900 poises spun through orifices having three limbs of length 0.020 inch and width 0.003 inch at a spinning speed of 608 f.p.m. and at a temperature of 288C and drawn under the same conditions as the above copolymer yielded a trilobal yarn having a modification ratio of 1.6.

EXAMPLES 5, 6 & 7

Copolymers of 6.6 and 6.T nylons together with polyhexamethylene suberamide (6.8 nylon), polyhexamethylene sebacamide (6.10 nylon) and poly(w-amino undecanoic acid) (11 nylon) as the third component were prepared and their softening points determined. Details of the compositions of the copolyamides and their softening points are given in Table 5.

Example 5 was prepared by the procedure described in Example 3, and Examples 6 and 7 by the procedure described in Example 2.

The polymer of Example 5 was melt-spun into a 5 filament yarn at spinning temperature of 288C and drawn over a hot plate at 120C at a draw ratio of 4.5. The drawn yam had a tenacity of 5.6 g/d, an extension at break of 13.0% and an initial modulus of 40.0

g/d/ 100% extension.

What we claim is:

1. A fibre forming copolyamide consisting essentially of the polymeric condensation product of (1) at least 50% by weight, based on the weight of the copolyamide, of hexamethylene diammonium adipate, (2) 20 by weight of hexamethylene diammonium terephthalate and (3) 2 20% by weight of epsilon caprolactam.

2. A fibre forming copolyamide consisting essentially of the polymeric condensation product of (l) at least by weight, based on the weight of the copolyamide, of hexamethylene diammonium adipate, (2) 20 40% by weight of hexamethylene diammonium terephthalate and (3) 2 20% by weight of hexamethylene diammonium suferate.

3. A ternary fibre forming copolyamide consisting essentially of (l) 20 40% by weight, based on the weight of the copolyamide, of hexamethylene terephthalamide units, (2) at least 50% by weight of hexamethylene adipamide units and (3) 2 20% by weight of W-amino undercarnide units.

TABLE 5 Copolymers of 6.6/6.T nylon with 6.8 6.10 & 11 nylon Example 5 6 7 Third component 6.8 6.10 l 1 Composition (66/6T/X) 62.9/26.3/ 56.0/32.3/ 58.4/33.7/

10.8 117 7.9 Softening point "C 260 253 257 Melt viscosity (poises) 2640 

1. A FIBRE FORMING COPOLYAMIDE CONSISTING ESSENTIALLY OF THE POLYMERIC CONDENSATION PRODUCT OF (1) AT LEAST 50% BY WEIGHT BASED ON THE WEIGHT OF THE COPOLYAMIDE, AND OF HEXAMETHYLENE DIAMMONIUM ADIPATE, (2) 20-40% BY WEIGHT OF HEXAMETHYLENE DIAMMONIUM TEREPHTHALATE AND (3) 2-20% BY WEIGHT OF EPSILON CAPROLACTAM.
 2. A fibre forming copolyamide consisting essentially of the polymeric condensation product of (1) at least 50% by weight, based on the weight of the copolyamide, of hexamethylene diammonium adipate, (2) 20 - 40% by weight of hexamethylene diammonium terephthalate and (3) 2 - 20% by weight of hexamethylene diammonium suferate.
 3. A ternary fibre forming copolyamide consisting essentially of (1) 20 - 40% by weight, based on the weight of the copolyamide, of hexamethylene terephthalamide units, (2) at least 50% by weight of hexamethylene adipamide units and (3) 2 - 20% by weight of W-amino undercamide units. 